\begin{table}[htbp]\centering
\def\sym#1{\ifmmode^{#1}\else\(^{#1}\)\fi}
\caption{Shift Heterogeneity Analysis}
\begin{tabular}{l*{2}{D{.}{.}{-1}}}
\toprule
            &Day Time Shifts      &Night Time Shifts    \\
            &\multicolumn{1}{c}{(1)}&\multicolumn{1}{c}{(2)}\\
\midrule
*** p$<$0.01, ** p$<$0.05, * p$<$0.1.} \\ \end{tabular} }
